Battle of Bayan Obo

The Battle of Bayan Obo occurred on 2 August 1937 when the Japanese 20th Infantry Division, led by Kaneharu Nakajima, invaded the Inner Mongolia region, which was ruled by the Xibei San Ma clique. The Japanese faced an enemy with almost eight times the amount of troops, but they managed to rout the Xibei San Ma forces before their Nationalist allies could arrive in force. The battle was one of the many battles fought between Japan and the rival Xibei San Ma clique over Inner Mongolia during the Second Sino-Japanese War, and more Japanese victories in Inner Mongolia would lead to the expansion of the Mengkukuo puppet state.